Regulated non-quarantine pest Project

NAME OF THE ORGANISM: Burkholderia caryophylli (Pseudomonas caryophylli) (PSDMCA)

GENERAL INFORMATION ON THE PEST

Name as submitted in the project specification (if different to the preferred name):

Pseudomonas caryophylli

Pest category:

Bacteria

1- Identity of the pest/Level of taxonomic listing:

Is the organism clearly a single taxonomic entity and can it be adequately distinguished from other entities of the same rank?

Yes

Is the pest defined at the species level or lower?:

Yes

Can listing of the pest at a taxonomic level higher than species be supported by scientific reasons or can species be identified within the taxonomic rank which are the (main) pests of concern?

Not relevant: Ornamental sector

Is it justified that the pest is listed at a taxonomic rank below species level?

Not relevant

Conclusion:

Candidate: Ornamental sector

2 – Status in the EU:

Is this pest already a quarantine pest for the whole EU?

No

Presence in the EU:

Yes

List of countries (EPPO Global Database):

Italy (1992)

Conclusion:

candidate

Justification (if necessary):

Data of the presence of this pest on the EU territory are available in EPPO Global Database (https://gd.eppo.int/).

HOST PLANT N°1: Dianthus (1DING) for the Ornamental sector.

Origin of the listing:

IIA2AWG

Plants for planting:

Plants intended for planting, other than seeds

3 - Is the pest already listed in a PM4 standard on the concerned host plant?

Yes

Conclusion:

Evaluation continues

Justification (if necessary):

Although the pest is listed in EPPO PM 4/2 Standard, evaluation continues because GB and the NL proposed deregulation of this pest/host combination in the replies to the RNQP questionnaire (possible candidate for management by industry).

4 - Are the listed plants for planting the main* pathway for the "pest/host/intended use" combination? (*: significant compared to others):

Yes

Conclusion:

Candidate

Justification:

Dianthus is mainly cultivated under a protected cropping system with strict sanitation processes that prevent infestation from the surrounding environment or previous crops. Burkholderia caryophylli is a bacterial pathogen and the host range of B. caryophylli includes the genus Dianthus and three other incidental, minor, hosts (statice, lisianthus and gypsophila). It is primarily spread through infected cuttings if no controls are in place, and outdoors the environmental conditions are not favourable to the pathogen and alternative hosts are not present, whereas in protected crops the cultural practices are very effective to keep the crop free from this bacterium. Only very short-distance spread within a crop is likely, and spread between different crops is unlikely.
B. caryophylli is unlikely to multiply in the soil in the absence of its host plants, and small populations are generally unlikely to establish in glasshouses, because of soil sterilisation between crops and/or use of soilless substrates and general hygiene practices. Crop rotation and/or sanitation procedures between cropping cycles will ensure that small populations do not become established in carnation production.

5 - Economic impact:

Are there documented reports of any economic impact on the host?

Yes

Justification:

B. caryophylli has caused serious damage in the USA since its first report in 1940. In the EU, no crop losses and no additional costs due to B. caryophylli have been reported in the last 25 years; therefore, the impact under current phytosanitary measures is considered minimal. In the absence of specific phytosanitary measures, the impact is expected to be minor to moderate. In the absence of any control measure (no certification, no sanitation and low hygiene in production sites), the impact expected would be major.

What is the likely economic impact of the pest irrespective of its infestation source in the absence of phytosanitary measures? (= official measures)

Minor

Is the economic impact due to the presence of the pest on the named host plant for planting, acceptable to the propagation and end user sectors concerned?

Yes

Is there unacceptable economic impact caused to other hosts (or the same host with a different intended use) produced at the same place of production due to the transfer of the pest from the named host plant for planting?

No

Conclusion:

Not candidate

Justification:

The industry already takes sufficient measures. It is not a problem thanks to voluntary certification schemes aimed at Fusarium prevention.